“It’s always hard to say the extent of the damage that could occur,” he says, adding existing infrastructure problems can exacerbate the effects of a storm. In the case of this atmospheric river, “it was a lot of elements lining up that caused so much damage at the time.”

The need to better understand and communicate the risks associated with certain types of weather was the impetus for a major overhaul of Canada’s weather alerting system.

Previously, alerts were issued when forecast conditions were expected to meet a certain threshold — such as winds gusting to 90 kilometres per hour or more, or more than 50 millimetres of rainfall in an hour. But most people have little to no frame of reference for what these hazards mean in practice, says Jesse Wagar, a warning preparedness meteorologist based at Environment and Climate Change Canada’s Edmonton weather office.

“We can talk about 10 centimetres of snow, we can talk about 90 kilometre-per-hour winds, but for the average person who’s going to experience this weather, it can be difficult to apply that information,” she explains. “What are 90 kilometre-per-hour winds? Is that strong enough to do damage?”

The new system, which launched at the end of 2025 and aligns with best practices set out by the World Meteorological Organization, instead uses different colours to alert the public to the expected impacts of the incoming weather, with yellow being the least severe but still impactful in the short term, orange for significant widespread impacts, and red for dangerous and life-threatening weather with extreme and long-lasting impacts. Under this new system, the B.C. atmospheric river would have been a red-level event, Wagar says. Ideally, that means everyone, from the public to municipal and provincial emergency managers, would understand the dangers posed by the incoming storm — and be ready to act.

So, the challenge facing Environment and Climate Change Canada’s meteorologists was to design an alert system that would be relevant and easy to understand no matter what type of severe weather is unfolding on any given day somewhere in the country. “Extreme cold” has a different definition in Iqaluit than it does in Toronto. Wagar hopes basing alerts on expected impacts instead of numerical criteria will help people better understand the risks associated with certain types of weather — and prepare accordingly. “We really want to be able to empower people to make those decisions to protect themselves.”

The other important factor in determining the level for an alert is confidence: how sure are Environment and Climate Change Canada’s forecasters that the weather is going to do what they think it’s going to do? In order for an orange or red alert to be issued, forecasters must be very confident that the event is going to have significant impacts. Wagar says today’s weather and climate models — computer simulations of the movements of the atmosphere used to predict the weather — are leagues beyond what they were even 15 years ago in terms of accuracy and precision. “We can tell you temperature trends several months out. We can see a big snowstorm coming next week. Is it going to be 10 centimetres or 20? As we get closer to the day, we can get more and more precise.”

A major advantage of the tiered system is that it gives meteorologists the flexibility to change an alert when new information becomes available as a result of on-the-ground observations. Wagar gives the example of a cold alert for Norman Wells, N.W.T. that was upgraded from yellow to orange when local authorities reported water pipes were freezing a few days into a prolonged period of temperatures in the low minus 40s in January. “There’s a lot of collaboration that goes on behind the scenes … to get an understanding of what the particular vulnerability of an area might be,” she says. “If there’s a widespread power outage going on and there’s a massive cold wave coming through, your vulnerability is higher, so that’s a big piece of that impact assessment.”

Once forecasters have determined an alert is needed, and the appropriate level for that alert, the next crucial step is to communicate it to the public. That’s where broadcasters like Kelsey McEwen come in. McEwen is the chief meteorologist for CTV Your Morning, where she delivers the daily forecast to a national audience and often breaks down unfolding severe weather events. Deciding what to focus on usually comes down to who is getting the worst weather — but “worst,” she’s learned, is relative.

According to Dave Sills, deputy director of the Canadian Severe Storms Laboratory at Western University in London, Ont., the purpose of a watch is to get people thinking about the possibility of an impactful storm before it’s upon them. “There are things you can do during that time [to prepare] that you wouldn’t be able to do later,” he says, such as securing loose items around your property that can become airborne during strong winds or making sure your family knows where to take shelter in the event that watch becomes a warning.

Under the new system, all tornado warnings will automatically be red level alerts. Sills, who also heads up the Northern Tornadoes Project, a major research initiative to improve the detection and prediction of tornadoes in Canada, is curious to see how the public will respond to that. Many people he’s talked to say the colour coding is intuitive, but he points out that when an orange blizzard warning was issued for London and other communities along the shore of Lake Huron in early February strongly advising people to stay off the roads, police still responded to dozens of collisions on the region’s highways. “You couldn’t make it any more clear that this is not a time to travel, so people also have to take up the message that is in these [alerts],” says Sills. “If you read that there’s going to be this risk of dangerous weather and you still are going out in it, there’s not much Environment and Climate Change Canada can do about that.”

McEwen agrees and says she’ll keep hammering home the difference between watches and warnings, even if it feels repetitive. “The difference between those two qualifications could mean the difference between somebody making a plan to go outside or cancelling. So I’ll say it over and over again if it means [keeping] somebody safe.”